An external device may be connected to an electronic device and, the electronic device may operate while using the external device. For example, a USB (registered trade mark) memory is connected to a USB connector of a personal computer (hereinafter also referred to a PC), and the PC writes data into the USB memory or the PC reads data from the USB memory. Upon detection of connection of an external device to the USB connector, the Operating System (OS) of the PC activates driver software corresponding to the detected device to thereby set up the external device so that the external device can be operable.
In recent years, a composite device provided with a USB hub and a plurality of devices in housing has been developed. Among the plurality of devices, a device or devices are unsuccessful in setup to be carried out by the OS. In such a case, it is necessary for the user to once unplug the composite device from the USB connector and insert the device again into the USB connector.